The present invention related to a triggered ignition system including an anti-reverse running control and particularly to an alternator driven triggered ignition system having a trigger signal generator coupled to the alternator.
With the advances in electronic technology, solid state triggered ignition systems have been developed for internal combustion engines. In low horsepower internal combustion engine applications, particularly two-cycle engine constructions, a capacitor discharge ignition system is desirable because the charged capacitor provides a relatively high voltage source which rapidly discharges through the solid state switch such as a controlled rectifier into the spark plug to produce reliable firing of the engine.
A particularly satisfactory solid state ignition system includes an alternator driven capacitor means with a triggered discharge circuit in combination with a trigger signal generator which is coupled to the alternator to provide a breakerless and distributorless multiple cylinder ignition system.
In small outboard motor and the like, the alternator and trigger generator are advantageously integrated and coupled to the engine shaft to provide the alternating charging source and trigger source in a compact configuration. A particularly satisfactory charging alternator with an integrated triggering signal generator is disclosed in the copending application of Sleder et al entitled "IGNITION BREAKERLESS AND DISTRIBUTORLESS MULTIPLE CYLINDER IGNITION SYSTEM" which was filed on Oct. 29, 1974 with Ser. No. 518,764.
An internal combustion engine is desirable started with a retard firing such that ignition occurs slightly after the piston reaches top dead center position. As the engine speed increases, however, the firing time should be advanced before top dead center position is reached. Although various electronic, as well as mechanical leverage systems have been suggested a highly satisfacotry advance means is shown in the above-entitled application, particularly where a relatively compact low profile is desired such as in low horsepower outboard motors.
The preferred embodiment of that disclosure includes an alternator built into the flywheel of a two-cylinder, two-cycle engine particularly adapted for application to an outboard motor. The main charging alternator includes an annular magnetic means secured within the flywheel skirt to form an annular rotor mounted concentrically of a stator assembly which is suitably mounted on the engine block. The rotor includes circumferentially extended and opposite polarized magnets with diametrically spaced polarity changeover points. The stator includes a semi-circular core concentrically mounted within the rotor and with charging coils and poles to the opposite core ends such that each movement of the magnetic changeover points past the coils generates capacitor charging pulses. A trigger coil is mounted, preferably in co-planar relation, between the charging coils and includes a separate pole aligned with the plane of the stator core but slightly spaced radially from the core. The trigger coil and pole are rotatably mounted in a housing having a cam which is coupled to and positions the throttle in accordance with the orientation of the housing about the stator core. The cammed housing is coupled through a suitable linkage to the throttle lever control and thus simultaneously adjusts the throttle setting and the angular position of the trigger coil which controls the timing of the engine.
Such low horsepower motors are widely constructed with pull start means wherein a starter cord is housed within a spring-loaded reel secured or otherwise coupled to the flywheel. The engine is started by rapidly pulling or extending the starter cord to spin the reel and thereby manually imparting rotation to the engine flywheel and crankshaft. When employing the integrated alternator, the starter actuation of course simultaneously provides for the corresponding operation of the alternator and trigger generator to provide the desired ignition to the engine.
Although engine driven alternators for charging of a capacitor and an integrated triggering generator provides a highly satisfactory ignition system, reverse running conditions have been encountered at starting, particularly with the application to relatively small compact two-cylinder engines such as employed in low horsepower, outboard motors.
Generally, the engine incorporated in an outboard motor or the like is designed to operate in a single, forward direction in order to properly rotate the propeller for propelling of the boat. If a reverse drive is desired, suitable reversing gears and the like can be provided. However, in such constructions it is important that the engines only operate in the forward direction in order to effect a proper controlled propulsion of the boat under reliable and complete control by the operator.